Power transmission assembly



Oct. 19, 1954 2,691,902

H. c. LYONS POWER TRANSMISSION ASSEMBLY Filed Feb. 6, 1953 2 Sheets-Sheet 1 IN V EN TOR.

ATTOQN EYS .1 H. c. LYONS POWER TRANSMISSION ASSEMBLY 2 Sheets-Sheet 2 Filed Feb. 6, 1953 7 3 5 m L 6 N 9 a l I.- 5m 8 2 3 53 m m l 1 a i 1 9 w. 8 i

a a m WW 2 s 3K 8 i w a H w e W 5 N a A Q i 7 6 m n INVENTOR. HoQAcE C. brows A TOQNEH'S ?atented Oct, 19, 1954 NITED STATES POWER TRANSIVIISSEON ASSEMBLY Horace C. Lyons, Tucson, Ariz.

Application February 6, 1953, Serial No. 335,481

2 Claims. l

This invention relates to power transmission assemblies and more particularly to a power transmission assembly for an engine mounted adjacent a vehicle drive axle and including a change speed gear or torque varying unit and a differential unit.

It is among the objects of the invention to provide an improved power transmission assembly in which a power plant, such as an internal combustion engine, is connected to one side of a differential unit, a change speed transmission or torque converter is connected to the differential unit opposite the power plant and a power or drive shaft extends from the power plant through the differential unit to the transmis-- sion unit or torque converter; which provides a unitary power transmission assembly in which the power plant and the change speed or torque varying unit are both rigidly connected to the differential unit, which eliminates the long drive shaft used in conventional vehicle power transmission mechanisms and provides a simplified power transmission assembly for a rear mounted vehicle engine; which facilitates the use of a two speed differential unit and provides an improved difierential unit of this character; and which is simple and durable in construction, economical to manufacture, and positive and efficient in operation.

Other objects and advantages will become apparent from a consideration of the following description and the appended claims in conjunction with the accompanying drawings wherein:

Figure 1 is a longitudinal cross sectional view through a power transmission assembly illustrative of the invention;

Figure 2 is a longitudinal cross sectional view on the line 2-2 of Figure 1;

Figure 3 is a longitudinal cross sectional View, similar to Figure 2, of a somewhat modified form of power transmission assembly; and

Figure 4 is a fragmentary cross sectional view on the line 44 of Figure 3.

With continued reference to the drawings and particularly to Figures 1 and 2, the numeral I generally designates a power plant, such as an internal combustion engine, having at one end a housing H which may constiute the clutch housing of such an engine. A friction clutch i2 is diagrammatically illustrated and is drivenly connected to the engine crank shaft in the usual manner. It is to be understood, however, that some other form of power transmitting mechanism, such as a fluid coupling, may be substituted for the friction clutch l2 without in any way exceeding the scope of the invention.

A differential unit, generally indicated at I3, and including a housing provided in two parts it and I5, is disposed adjacent the end of the engine housing I I and the differential unit housing is rigidly secured to the engine housing. In the arrangement illustrated, the parts of the differential housing are provided with complementary formations providing a flange it which overlies the end of the engine housing H and is secured to the latter by suitable means, such as the bolts or cap screws ii, extending througi'i corresponding apertures in the flange i5 and threaded into corresponding tapped holes in the engine housing. A gasket i8 is interposed between the flange It and the adjacent surface of the engine housing to provide a lubricant tight seal between the engine housing and the housing of the differential unit.

The two parts Hi and I5 of the differential housing are separable along a plane extending from one end of this housing to the other end and are rigidly secured together by suitable means, such as the bolts l9 extending through registering apertures in complementary flanges 20 extending along the edges of the two parts of the differential housing.

At its opposite ends with the differential housing is provided with end walls 2i and 22 and these end walls are formed to provide annular bearing receptacles 23 and M respectively. An antifriction bearing 25 is mounted in the receptacle 23 and a similar antifriction bearing 26 is mounted in the receptacle 24. A tubular quill shaft 2'? is journaled near its respectively opposite ends in the bearings 25 and 26 and this quill shaft has annular formations 2s and 255 thereon providing shoulders which respectively engage the inner races of the bearings 25 and 2&3 to hold the quill shaft against longitudinal. movement relative to these bearings and to also hold the bearings in the corresponding receptacles 23 and 24.

The two parts it and i5 of the differential housing are provided respectively with outwardly projecting hollow bosses 30 and 35 to which the inner ends of tubular axle shaft housings are respectively connected and each of these bosses is annularly recessed at its inner end to provide a seat or receptacle for an antifriction bearing. An antifriction bearing 32 is mounted in the seat 33 provided in the boss 39 and a similar antifriction bearing 34 is mounted in the seat 35 provided in the boss 3!.

A ring gear 35 is disposed in the differential housing and a tubular hub 3! projects coaxially from one side of the ring gear and is received 3 at its end remote from the ring gear in the antifriction bearing 32, and at its other end this hub has an annular flange formation 33 which bears marginally against the side of the ring gear remote from the bearing 32.

A cup shaped spider gear housing 49 is disposed at its open end against the side of the flange formation 38 remote from the ring gear 36 and has at its end remote from the ring gear a hollow hub 41 received in the inner race of the bearing 34 and provided with an annular shoulder 42 which bears against the inner race of this bearing to maintain the bearing seated in the seat formation 35. The ring gear 36, the hub 3! and the spider gear housing 4% are rigidly connected together by the rivets 38 and provide a unitary structure extending transversely of the transmission housing and journaled at its opposite ends in the bearings 32 and 34.

The housing 40 is made in two separable parts, both of which are provided with semicircular notches in their mutually opposed edges which notches constitute bearing apertures in the housing when the two parts are secured together in operative assemby and the part nearest the ring gear has at its end disposed against the flange formation 38 on the hub 37 an external annular flange 44, through which the rivets 39 extend. A spider gear axle 43 is mounted near its respectively opposite ends in the apertures thus provided in the spider gear housing. The two parts of the housing are secured together by suitable means, such as the cap screws 4 which may extend through the outer part of the housing and be threaded into tapped holes provided in the inner part of the housing to secure the two parts of the housing together.

Spider gears 45 and 46 are journaled on the axle 43 within the housing 40 and near the respectively opposite ends of the axle. An axle coupling pin 41 extends through and is journaled in the tubular hub 37 and carries on its end within the housing 40 a differential gear d3 which meshes with the two spider gears 45 and 46. The other end of this axle coupling pin is disposed within the boss 30 and provided with a spline formation 49 for connecting the coupling pin to an axle shaft or corresponding driven element.

A second axle coupling pin 50 extends'through and is journaled in the hollow hub ll of the housing 40 and carries on its end Within the housing a differential gear which also meshes with the spider gears 45 and dB. The other end of this second coupling pin is disposed within the boss 3| and provided with a spline formation 52 for connecting this coupling pin to a corresponding axle shaft or equivalent driven element.

A pinion gear 53 is provided on the quill shaft 27 near the bearing 25 and meshes with the ring gear 36 to drive the differential mechanism when the quill shaft is driven.

It is to be understood that the differential mechanism is somewhat diagrammatically illustrated and described and may be structurally modified without in any Way exceeding the scope of the invention. For example, while only two spider gears are illustrated and described, it is to be understood that three or more spider gears may be utilized if considered advisable.

The quill shaft 2'! preferably extends through the differential unit above the ring gear hub 31 so that the rotational axis of the pinion gear 53 does not intersect the rotational axis of. the ring The gears 33 and. 53 are, therefore; hyp'oid gears with the pinion gear above a substantially horizontal plane including the axis of rotation of the ring gear. This permits a higher mounting for the rear mounted engine, giving greater road clearance for the vehicle and more efficient operation.

A drive shaft 54 extends through and is journaled in the tubular quill shaft 21 and projects at one end into the engine housing ll through an aperture 55 in the end of this housing. This drive shaft is provided within the housing ii with a spline formation 56 by means of which it is drivenly connected to the vehicle clutch I? or equivalent power delivery mechanism.

A change speed gear or transmission housing 57 is disposed at the end of the differential mechanism opposite the engine housing I i and has an end wall 5-8 disposed against the adjacent end wall 22 of the differential housing. The transmission housing is rigidly secured to the differential housing by suitable means, such as the cap screws 59,. extending through corresponding apertures in an annular flange 68 on this end of the differ ential housing and threaded into corresponding tapped holes in the end wall 58 of the transmission housing. A gasket BI is interposed between the end wall 22 of the differential housing and the end wall 58 of the transmission housing to provide a lubricant tight seal between these two housings and the drive shaft 54 projects through an aperture 52 in the end Wall 58 and into the transmission housing.

Where a change speed gear transmission, as

indicated in the accompanying drawings, is utitransmission housing 51 with a spline formation 83 and a transmission gear 64 is mounted on this spline formation and will mesh with a gear of the usual cluster gear, not illustrated, for driving the quill shaft at various speed ratios. I

The drive shaft 54 is provided adjacent the end of the quill shaft within the transmission housing 5? with a spline formation 65 and a gear 55 is slidably mounted on this spline formation and will cooperate with the above mentioned cluster gear to provide one of the transmission speed ratios. The gears 64 and 66 are provided on their mutually adjacent faces with clutch formations 87 and 68 respectively which can be engaged by sliding the gear 66 along the spline formation 65 of the drive shaft toward the gear 6 3 to provide a direct drive from the drive shaft 54 to the quill shaft 21.

While a change speed gear transmission has been diagrammatically illustrated and described above, it is to be understood that the invention is not limited to this particular type of torque varying mechanism, but that a hydraulic torque converter, an automatic transmission, or other torque varying mechanisms may be utilized withoutin any way exceeding the scope of the invention to drivingly connect the drive shaft 54 to the quill shaft 27 and prov-idethe necessary torque variation for operation of the vehicle.

The modified arrangement illustrated in Figures 3 and 4 may utilize the same power plant and the same torque varying unit, but includes a two speed differential mechanism. In this arrangeinent, the differential unit, generally indicated' at '70, has a housing provided in two separable parts- 1! and 12 secured together the same manner as the two" parts ofthe housing l3, illustrated in Figures I and 2 and described above, and providing end walls 73 and M of which the end wall? it is disposed against the end. of the engine housing I I and secured thereto by the cap screws 1'! with the gasket I8 interposed between the housing II and the end of the differential unit housing to provide a lubricant tight seal between these housings. The end wall 74 of the differential housing is disposed against the corresponding end wall 58 of the transmission housing unit 5? and secured thereto by the bolts 59, a gasket 5! being interposed between these two end walls to provide a lubricant tight seal.

The end wall 13 is provided with an annular bearing receptacle I5 receiving an antifriction bearing 76 and a pinion gear 7? has a tubular hub I8 extending through and journaled in the bearing I6, the end of the hub I8 remote from the gear 11 being provided with dog clutch teeth 19.

The end wal1 14 of the differential housing is provided with an annular bearing receptacle 30 and an antifriction bearing 8! is mounted in this receptacle. A pinion gear 82, smaller than the pinion gear I7, is disposed within the differential unit housing and has projecting from one end a tubular hub 83 which extends through and is journaled in the bearing BI.

A bearing support or receptacle '84 extends inwardly of the wall of the differential unit housing and carries two spaced apart antifriction bearings 85 and 8t. The pinion gear TI is provided at its end remote from the hub I8 with a tubular hub formation 87 received in the bearing 85 and the pinion gear 82 is provided at its end remote from the hub 33 with a tubular hub 88, the end of which remote from the pinion gear 32 is received in the bearing 55. The two pinion gears Ti and 82 and their hubs extend longitudinally of the differential unit housing from one end to the other of this housing and through the opposite end walls thereof and have a common axis of rotation.

A drive shaft 89 extends through and is journaled in the two pinion gears 11 and '32 and extends at its opposite ends beyond the distal ends of the hub formation 18 and 83.

The differential unit housing part 'II is provided with an outwardly projecting hollow boss 90 having at its inner end a bearing seat formation BI and an antifriction bearing 92 is seated in the bearing seat 9i. The housing part 12 is provided with an outwardly projecting hollow boss 33 provided at its inner end with a bearing seat formation 94 and an antifrictio-n bearing 95 is mounted in the seat M. The bosses 90 and =93 receive the inner ends of tubular axle shaft housings or equivalent structural elements, not illustrated.

Two ring gears 86 and *9! are disposed in the differential unit housing in spaced apart and substantially parallel relationship to each other and are connected together by a common, tubular hub 98 extending therebetween. The hub 98 is provided with spaced apart annular flanges I00 and IUI disposed at the outer sides of the ring gears 96 and 9'! respectively, and marginally overlying the ring gears. The flanges it!) and lili are provided with angularly spaced apart peripheral notches, as indicated at I92 for the flange I 0|, providing therebetween angularly spaced apart, apertured lugs, as indicated at I83, and the ring gears are provided in their inner edges with spaced apart notches, as indicated at I04 for the ring gear 9?, providing therebetween angularly spaced apart apertured lugs as indicated at I05, which pass through the notches in the corresponding hub flanges as the ring gears are being assembled with the hub, the hub flange lugs also passing through the notches in the corresponding ring gears. After the hub flanges have been passed through the corresponding ring gears, the gears are rotated relative to the flanges until the corresponding lugs are superposed and the lugs are secured together by the rivets I06. At one end the hub '98 has a hub formation II)? projecting outwardly and received in the antifriction bearing 95.

A cup shaped spider gear housing III] is secured at its open end to the hub flange Ifiil at the side of this flange remote from the ring gears 96 and 97 and the housing [I0 has at its end remote from the ring gear 96 a hollow hub IIZ received in the antifriction bearing 92 to support the housing IHB on the differential unit housing part II. 7 3' The housing M0 is provided in two separa e parts which are connected together and secured to the hub flange I00 by suitable Cap screws H3 and the two parts of this housing are provided with notches which are aligned where the two parts are secured together to provide apertures receiving respectively opposite ends of a spider gear axle H5. Spider gears H5 and H7 are journaled on the axle H5 and disposed within the housing IIIl, one near each end of the axle, and a coupling pin IIS extends through the hub 98 into the housing II I] and carries on its end within the housing III! a differential gear I26 which meshes with the spider gears H6 and I I7. The coupling pin IIS projects at its other end into the boss 93 and is there provided with a spline formation i2I for connecting this coupling pin to an axle shaft or equivalent driven member.

A second coupling pin I22 extends through the hub I if on the housing I If! into this housing and is provided at its end within the housing I I0 with a difierential gear I23 meshing with the spider gears. This second coupling pin extends into the boss 98 and is provided at its end within this boss with a spline formation I24 for connecting this second coupling pin to an axle shaft or equivalent driven element.

The pinion gear 'il meshes with the ring gear 96 and the pinion gear 82 meshes with the ring gear 91, the gear ratio between the pinion H and ring gear iiii being less than the ratio between the pinion 82 and the ring gear ill so that the transmission unit will have two speeds depending upon which of the pinion gears is transmitting power to the associated ring gear.

In order that each pinion gear may mesh with its associated ring gear without interfering with the other ring gear, the rotational axis ofthe pinion gears TI and 82 and of the drive shaft 89 is shown as slightly inclined relative to the rotational axis of the two ring gears 96 and ill and the differential mechanism. In the arrangement illustrated, the angle between the two axes of rotation is between and degrees, but it is contemplated that the two axes may be disposed substantially at right angles to each other, if desired, by properly designing the ring gears and pinion gears for this purpose.

It is contemplated that in the arrangement illustrated, the pinion gear 11 and ring gear 98 will constitute an overdrive or high speed drive for the vehicle and that only a releasable direct driving connection between the pinion gear I? and the drive shaft 89 will be required. Such a direct driving connection is provided by a dog clutch element I25 slidably mounted on the splined end portion I26 of the drive shaft 89 7 within the engine housing I I, the clutch element I25 being provided with clutch teeth I27 which engage with the clutch teeth I9 on the adjacent end of the pinion gear hub 18 to provide a direct driving connection between the drive shaft 89 and the pinion gear TI. Suitable means, not illustrated, are provided for moving the clutch element I25 and this control means is so coordinated with the change speed transmission or torque varying mechanism that the two pinion gears 17 and 82 cannot be connected to the drive shaft 89 at the same time.

A transmission gear [30 is provided on the end of the pinion gear hub 83 projecting into the transmission housing 51 and the drive shaft 30 is provided within the transmission housing with a spline formation I3I.

A shiftable transmission gear I32 is slidably mounted on the spline formation I3I of the drive shaft 89 and the gears I30 and I32 are provided on their mutually adjacent sides with clutch teeth I33 and I34 respectively which intermesh when the gear I32 is moved toward the gear I30 to provide a direct driving connection between the drive shaft 89 and pinion gear 82.

The change speed gear transmission illustrated will include the usual cluster gear, not illustrated, driven by the drive shaft I3I at various selected speed ratios and driving the pinion gear 82 through the gear I30. It is to be understood, however, that other forms of torque varying devices may be used in substitution of the change speed gear transmission, if desired.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are, therefore, intended to be embraced therein.

What is claimed is:

1. In combination with a power plant and a torque varying unit, a differential unit comprising a housing having oppositely disposed ends secured one to said power plant and the other to said torque varying unit, antifriction bearings mounted one in each end of said housing, antifriction bearings mounted in said housing between the ends thereof, a first pinion gear jour- 8 naled at one end in the bearing in the power plant connected end of said housing and journaled at its other end in a bearing between the ends of said housing, a second pinion gear journaled at one end in the bearing in the end of said housing adjacent said torque varying unit and journaled at its other end in a bearing between the ends of said housing, said pinion gears having mutually aligned bores therethrough, a drive shaft extending through said pinion gears drivingly connecting said power plant to said torque varying unit, clutch means acting between said drive shaft and said first pinion gear for drivingly connecting the latter to said drive shaft, means drivingly connecting said torque varying unit to said second pinion gear, interconnected ring gears disposed in said housing and meshing respectively with said pinion gears, differential mechanism secured to said ring gears, and means journaling said ring gear and differential mechanism assembly in said housing, said pinion gears and associated ring gears providing different gear ratios.

2. In combination with a power plant and a torque varying unit, a differential unit comprising a drive shaft extending between and drivingly connecting said power plant to said torque varying unit, a first pinion gear mounted on said shaft for rotation therearound adjacent said power plant, a second pinion gear mounted on said shaft for rotation therearound adjacent said torque varying unit, interconnected ring gears meshing respectively with said pinion gears, a diiferential mechanism secured to said ring gears, clutch means acting between said drive shaft and one of said pinion gears for drivingly connecting the latter to said drive shaft, and another clutch means acting between said drive shaft and the other of said pinion gears for drivingly connecting thelatter to said drive shaft,

said pinion gears and associated ring gears providing different gear ratios.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,864,992 Fatland June 28, 1932 1,938,201 Wells Dec. 5, 1933 2,000,605 Moorehouse May 7, 1935 2,075,084 Best Mar. 30, 1937 2,105,742 Lee Jan. 18, 1938 2,110,021 Kliesroth Mar. 1, 1938 

